A backyard pond doesn't have to be a major excavation project. If your terrain is rocky or the water table in your area is too high, you may not easily sink the pond. Above ground ponds are the solution. They can be as elaborate as any sunken pond but they may also be as casual as an old galvanised tub with a few goldfish or a wooden barrel sitting on the terrace.
An above ground pool at the edge of the patio provides seating on the wide capstone edge and works even in high water table areas. The pond is constructed the same way a sunken pond is, only the dug pit is extremely shallow or nonexistent, depending on the pond's depth and the terrain. An attractive and vibrant backyard water feature uses mortared stone walls for endurance and stability, a built-up corner for a bio-filter and waterfall and plenty of plants in and outside the pond to integrate it into the landscape. The waterfall aerates the pond, creates a musical background for patio activities, is visually appealing and helpful in keeping a fishpond clean. Water lilies, reeds and ornamental grasses provide some shade for fish, platforms for tiny frogs and a place for pricey Koi and carp to hide from predatory birds.
Whether your pond is entirely above ground or partly sunken with built-up walls, where you put it will determine its success or failure. Begin planning by looking for spots that can be seen from the house. The pond should be an enjoyable part of the landscape even when you aren't sitting outside next to it. Visibility is key for discouraging predators as well. Pick a spot that predatory animals and birds won't like -- the more open the better. If you will plant shrubs as a shade or windbreak, take the interrupted sightlines into account when seating the pond. Try to locate the pond close to water and power lines for ease of maintenance. Calculate the sun carefully. Ponds need several hours of sun daily for plant photosynthesis and oxygen production. However, intense midday sun can lead to unwanted algae blooms. If a tree or bush provides shade, ensure it doesn't shed leaf litter into the water.
An above ground pond doesn't have to be rock-lined; it can be as simple as a wooden half-barrel. Place a preformed pond basin or a reclaimed wooden half barrel in a terrace or patio location that gets five or six hours of sun each day. The sun is necessary for water clarity and plant survival. The finished pond will be too heavy to move, so get this step right. A barrel can be lined with a heavy-duty pond liner or just thoroughly cleaned to eliminate all brewing residue and then filled with water so the seams swell to make it watertight. If you use a square or rectangular pond basin, a wood frame outside looks good on a patio. Cedar or teak will silver as it ages, and redwood is a durable choice. Use a submersible pump in the pond to keep the water clean, and get one powerful enough to filter fish debris and pump water to the top of a waterfall. Plant just a few pots of grasses in a small pond and one or two water lilies for water health and balance.